Method and apparatus for attaching crossmembers to a pair of flanged beams

ABSTRACT

A pair of elongate attachment members, or “Z-rails” for attaching an end of a trailer crossmember to a flanged beam each include a first end section, an L-shaped portion comprising a horizontal leg and a vertical leg extending from the first end section, and a second end section extending from the vertical leg. The horizontal leg has a bottom surface with a width equal to the distance between the web of the flanged beam and the end of the flange. The vertical leg has an outer surface with a width equal to the width of the end of the flange. The Z-rails are attached to opposite ends of the crossmember to form a subassembly. The subassembly is fixed to and between the flanged beams by welding the first end sections to the web of the corresponding beam, with the horizontal leg on the flange, without directly heating the flange, thereby not diminishing the toughness of the flange.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of application Ser. No. 16/189,975,filed Nov. 13, 2018, the entire disclosure of which is herebyincorporated by reference herein.

BACKGROUND

Commercial trailers, for example, full trailers and semi-trailers, arewell known in the art and are produced and configured in various stylesand for a wide variety of industries to accommodate the particulartrailering needs of different applications. For example, WesternTrailers® brand trailers, by Western Trailer Co. are available asplatform trailers (for example, flatbed, drop deck or step-frame, andhopper flat trailers), agricultural trailers (for example, commoditybelt, express floor, and hopper flat trailers), forest industry trailers(for example, chip and express floor trailers), curtainsider trailers or“tautliners,” and specialty trailers for the military, aerospace, glass,and wind power industries. The most common type of trailers is box orvan trailers.

Conventionally, a semi-trailer includes one or more (typically more)rear axles and a front end that is configured to be supported by theprime mover (tractor), or in the case of an additional towed trailer,supported by a trailer dolly. Full trailers include one or more frontaxles and one or more rear axles that support the trailer.

The chassis (or frame) of a platform (or flatbed) trailer typicallyincludes two parallel main beams that extend along all or substantiallyall of the length of the trailer, and a plurality of connectingcrossmembers that are fixedly attached to the main beams to produce asturdy frame. The chassis provides a support structure for other trailercomponents, including for example, suspension components, a trailerstand, a fifth-wheel kingpin coupling, and the like.

In some embodiments the main beams are tempered steel beams, forexample, I-beams, channel beams, or the like. In other embodiments themain beams may have a different cross-section shape, for example,C-shaped or channel beams. In other embodiments the main beams areformed from other metal or metal alloys, for example, heat-treated, ortempered, aluminum alloys.

In prior art trailers the crossmembers are welded directly to the mainbeams, to produce a fixed and permanent connection that can withstandthe rigors and miles that the trailer is expected to encounter. However,heating the tempered metal by welding can weaken the main beams locallyby interfering with the design tempering of the beams. Frequently, aplurality of crossmembers are fixed to the main beams in relativelyclose spacing, for example, to provide a mounting and support structurefor a particular trailer component, such as a coupler assembly, asuspension assembly, or the like. Sequentially welding a plurality ofcrossmembers to the main beams may result in significant de-tempering inthe impacted region of the main beams due to the heating of the mainbeams over a longer installation period. Welding multiple crossbeams tothe main beams within a short distance can also be difficult for thewelder who must accurately position the crossmembers sequentially whileworking around earlier-installed crossmembers.

It is desirable to weld crossmembers to the main beams of trailers in amanner that would reduce interference with the engineered tempering ofthe main beams, and that would allow a plurality of crossmembers to beinstalled in a single installation.

SUMMARY

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This summary is not intended to identify key features ofthe claimed subject matter, nor is it intended to be used as an aid indetermining the scope of the claimed subject matter.

A method for fixing a crossmember to a vehicle frame having a flangedfirst beam and a flanged second beam, wherein the beam flange has anupper surface with a first width and an end surface having a secondwidth, includes fabricating a crossmember assembly by fixing a firstelongate attachment member (“first Z-rail”) to one end of thecrossmember and fixing a second elongate attachment member (“secondZ-rail”) to an opposite end of the crossmember. The Z-rails each include(i) a first end section, (ii) an L-shaped portion comprising ahorizontal leg extending from the first end section and a vertical legextending from the horizontal leg, and (iii) a second end sectionextending from a bottom end of the vertical leg. The horizontal leg ofthe L-shaped section defines a lower surface having a width equal to theflange first width and the second leg defines an outer surface having awidth equal to the flange second width. The method includes positioningthe crossmember subassembly on the first and second flanged beams suchthat the horizontal leg of the first Z-rail abuts the first surface ofthe first beam flange and the vertical leg of the first Z-rail abuts theend surface of the first beam flange, and such that the horizontal legof the second Z-rail abuts the first surface of the second beam flangeand the vertical leg of the second Z-rail abuts the end surface of thesecond beam flange. The method further includes welding the first endsection of the first Z-rail to the web of the first beam withoutdirectly heating the first beam flange, and welding the first endsection of the second Z-rail to the web of the second beam withoutdirectly heating the second beam flange.

In an embodiment the first beam and the second beam comprise I-beams orchannel beams.

In an embodiment a plurality of crossmembers are attached to the beam,and the method includes fixing all of the plurality of crossmembers tothe first and second elongate attachment members.

In an embodiment the first Z-rail second end section is perpendicular tothe first Z-rail vertical leg, and a bottom surface of the first Z-railsecond end section is coplanar with a bottom surface of the flange ofthe first beam.

In an embodiment fabricating the crossmember subassembly includesbolting the crossmember flange to the second end section of the firstand second Z-rails.

In an embodiment the method includes bolting the L-shaped portion of thefirst Z-rail to the first beam flange and bolting the second Z-rail tothe second beam flange.

In an embodiment the second end sections of the first and second Z-railsinclude a first portion and a second portion, wherein the second portionis spaced apart from the first portion.

An elongate attachment member for attaching an end of a crossmember to amain beam of a trailer, wherein the main beam having a web portion and aflange extending away from the web portion, wherein the flange definesan upper surface having a first width and an end surface having a secondwidth includes a first end section, an L-shaped portion comprising ahorizontal leg extending from the first end section and a vertical legextending from the horizontal leg, and a second end section extendingfrom a bottom end of the vertical leg. The horizontal leg defines alower surface having a width equal to the first width and the verticalleg of the L-shaped portion defines an outer surface having a widthequal to the second width.

In an embodiment the elongate attachment member is configured to attacha plurality of crossmembers to the main beam.

In an embodiment the second end section is perpendicular to the verticalleg of the L-shaped portion, and the first end section is perpendicularto the horizontal leg of the L-shaped portion.

In an embodiment the horizontal leg is configured to be bolted to theflange and the second end section is configured to be bolted to thecrossmember.

In an embodiment the second end section comprises a first portion and asecond portion spaced apart from the first portion.

DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of thisinvention will become more readily appreciated as the same become betterunderstood by reference to the following detailed description, whentaken in conjunction with the accompanying drawings, wherein:

FIG. 1 illustrates a conventional frame structure for a trailer havingopposed main beams and a plurality of crossmembers;

FIG. 2A is a perspective view of a crossmember subassembly fixed to leftand right main beams using Z-rails in accordance with the presentinvention;

FIG. 2B shows the crossmember subassembly shown in FIG. 2A with the mainbeam shown spaced away;

FIG. 3 is a perspective view of one of the Z-rails shown in FIG. 2B;

FIG. 4 is a sectional view of the crossmember subassembly and main beamthrough section 4-4 indicated in FIG. 2A;

FIG. 5 is a detail front view of one side of the crossmember subassemblyand associated main beam shown in FIG. 2A;

FIG. 6A is a perspective view of a crossmember subassembly with asuspension crossmember attached to a second embodiment of Z-rails inaccordance with the present invention;

FIG. 6B is a section view of the crossmember subassembly shown in FIG.6A attached to a main beam of the trailer and illustrating a suspensionassembly; and

FIG. 6C is a detail view of the crossmember subassembly indicated bydetail box C in FIG. 6B.

DETAILED DESCRIPTION

FIG. 1 illustrates a vehicle trailer frame 91 for a conventional trailer90. The trailer frame 91 includes two main beams 92 that are paralleland extend substantially along the length of the trailer 90. The mainbeams 92 are connected with a plurality of crossmembers 93 thatcooperatively define the structural frame 91, and provide variouscomponents or support for such components. Additional crossmemberassemblies include a kingpin assembly 95, support legs 96, a suspensionassembly (not shown), and the like, as are known in the art.

The main beams 92 provide the primary support structure for the trailer90 on the axle assemblies 98 (three shown), and must support significantdynamic loads encountered during operation of the trailer 90. The mainbeams 92 are typically flanged steel or aluminum alloy beams, forexample, I-beams (with an upper flange, a lower flange, and a webportion connecting the upper and lower flanges), channel or C-beams,W-beams, or the like. The dynamic loads produce bending moments on thebeam that are substantially reacted in the beam 92 flanges. In order towithstand and react these loads the main beams 92 are generally heattreated to provide a desired combination of strength and ductility,sometimes referred to as the toughness of the beams.

To achieve a desired toughness the beams 92 may initially be hardenedusing a quenching process wherein the beams 92 are heated to apredetermined temperature and then cooled in a rapid and controlledquenching process. After quenching, the beams are typically undesirablyhard and brittle due to Martensite formed in the steel during thequenching process. The beams are therefore tempered to reduce thebrittleness of the steel. Tempering involves heating the hardened steelto a prescribed temperature selected to achieve the desired toughness,which may be defined as the ability of the steel to absorb energy anddeform without fracturing. The heating/tempering process is carefullycontrolled to achieve the desired toughness.

In prior art frames, the construction of the frame 91 typically includeswelding some or all of the crossmembers to the main beams 92. However,heating the main beams 92 during welding can undermine the temperingprocess, changing the local toughness properties of the main beam 92,which can lead to premature failures.

FIG. 2A is a perspective view showing portions of a left main beam 92Land a right main beam 92R. A crossmember subassembly 120 is fixed to themain beams 92L, 92R. In this exemplary embodiment the main beams 92L,92R are I-beams, for example, wide flange I-beams, each beam 92L, 92Rhaving an upper flange portion 92UF, a lower flange portion 92LF, and aweb portion 92W. The crossmember subassembly 120 is fixedly attached tothe main beams 92L, 92R. The crossmember subassembly 120 includes aplurality of crossmembers 122 (four shown) that are fixedly attached totwo oppositely disposed shaped attachment plates, referred to herein asZ-rails 100. The crossmembers 122 in this example provide support for akingpin assembly (not shown). A corresponding view of the crossmemberassembly 120 exploded from the main beams 92R, 92L is shown in FIG. 2B.

The crossmembers 122 are fixed to the Z-rails 100 in any convenientmanner, for example, by welding, or with welding and attachment bolts.The crossmembers 122 are fixed to the Z-rails 100 before the crossmembersubassembly 120 engages the main beams 92L, 92R. Therefore, welding thecrossmembers 122 to the Z-rails 100 can be accomplished without causingany heating of the main beams 92L, 92R, avoiding any potentially adverseimpact on the toughness of the tempered main beams 92L, 92R. Inaddition, the Z-rails simplify construction of the trailer by enablingthe separate construction of unitized crossmember subassemblies (such assubassembly 120) that are attachable as a unit to the main beams 92L,92R.

The crossmember subassembly 120 is positioned at a desired location onand between the lower flange portions 92LF of the main beams 92L, 92R,and is fixed to the main beams 92L, 92R, as discussed below. In someembodiments the crossmember subassembly may further include one or twoupper Z-rails 100 fixed to an upper end of one or more associatedcrossmembers, with the upper Z-rails oriented to engage the upper flangeportions 92UF of the main beams 92L, 92R.

The Z-rails 100 will now be described in detail, with reference to FIG.3 showing a perspective view of the Z-rail 100 in isolation. The Z-rail100 is configured to engage a corresponding one of the main beams 92L or92R. Although in the embodiment of FIG. 3 the Z-rail 100 is configuredto attach to an I-beam, in other embodiments the Z-rail may be readilyadapted to engage other flanged beams, including beams having adjacentportions or faces that are not perpendicularly disposed. The Z-rail 100includes an upper vertical flange 102, an L-shaped middle portioncomprising a horizontal leg 104 and a vertical leg 106, and a lowerhorizontal flange 108. The Z-rail 100 upper vertical flange 102 isoriented at a right angle to the horizontal leg 104, the horizontal leg104 is oriented at a right angle to the vertical leg 106, and thevertical leg 106 is oriented at a right angle to the lower horizontalflange 108. The bottom face 103 of the horizontal leg 104 has a width L1that is equal to the horizontal distance L1 from the web 92W to an innerface 94 of the main beam lower flange 92LF (see FIG. 2A). The outer(left) face 105 of the vertical leg 106 has a width L2 that is equal tothe width L2 of the main beam lower flange 92LF (see FIG. 2A).Therefore, as seen most clearly in FIG. 2A, the upper vertical flange102 abuts the main beam web 92W of the main beam 92L when the verticalleg 106 abuts the inner face 94 of the lower flange 92LF, and the lowerhorizontal flange 108 is substantially co-planar with a bottom face ofthe main beam 92L lower flange 92LF.

FIG. 4 is a sectional side view through section 4-4 indicated in FIG.2A. As described above the crossmember subassembly 120 is preassembledwith the lower ends of the crossmembers 122 welded 115 (or otherwisefixed) to the Z-rails 100 prior to engaging the main beams 92L, 92R. Thecrossmember subassembly 120 is then positioned between and engaging themain beams 92L, 92R such that the upper vertical flanges 102 ofcorresponding Z-rails 100 abut corresponding main beam webs 92W. TheZ-rail 100 upper vertical flange 102 is then welded 114 to thecorresponding main beam web 92W. As shown in FIG. 4, optionally an upperportion of the crossmembers 122 may be welded 116 directly to the mainbeam web 92W.

It will be appreciated by persons of skill in the art that the risk offracture in the main beams 92L, 92R is primarily in the upper and lowerflanges 92UF, 92LF, and that the toughness properties in the web 92W istypically not a concern. Therefore, a loss of temper or toughness in theweb 92 due to welding the Z-rails 100 and the crossmembers 122 to theweb 92W is of secondary consideration. The Z-rails 100 allowcrossmembers 122 to be fixedly attached to the main beams 92L, 92Rwithout directly heating the flanges 92LF, 92UF of the main beams 92L,92R, and therefore without compromising the tempering of the flanges,and therefore without reducing local toughness properties of the mainbeams 92L, 92R.

FIG. 5 is a detail front view showing the right side of the assemblyshown in FIG. 2A, and further including optional first bolt assembly 110and optional second bolt assembly 112. In this embodiment, the lowerflanges 124 of the crossmembers 122 are bolted to the lower horizontalflange 108 of the Z-rails 100 with the first bolt assembly 110. Thebolted connection may be used rather than, or in addition to, the weldedconnection 115 shown in FIG. 4. In this embodiment the Z-rail 100 mayalso be bolted to the lower flange 92LF of the main beam 92R with thesecond bolt assembly 112, which extends through the horizontal leg 104of the Z-rail 100.

FIGS. 6A-6C illustrate another embodiment showing a pair of Z-rails 200mounting a crossmember 99 for a trailer suspension assembly 80 to mainbeams 92L, 92R. FIG. 6A shows a crossmember subassembly 220 including aprior art suspension crossmember 99 fixed to a pair of parallel,spaced-apart Z-rails 200. Each of the Z-rails 200 in this embodimentinclude an upper vertical flange 202, and an L-shaped portion comprisinga horizontal leg 204 and a vertical leg 206 extending from the uppervertical flange 202, similar to the corresponding portions of the Z-rail100 shown in FIG. 3. A lower horizontal flange 208 (FIG. 6B) extendsfrom the vertical leg 206 and comprises a first portion 208A and asecond portion 208B (FIG. 6C). The first and second portions 208A, 208Binclude apertures configured to engage suspension components 82, 83positioned below the Z-rails 200, as shown in FIG. 6B which shows thesuspension assembly 80 located substantially below the Z-rails 200.

Referring to the detail view in FIG. 6C, the upper vertical flange 202of the Z-rail 200 is welded 214 to the main beam web 92W, and thesuspension crossmember 99 is also welded 216 to the main beam web 92W.Neither the Z-rail 200 nor any of the suspension components (e.g.,crossmember 99) are welded to the main beam lower flange 92LF. Secondbolt assemblies 112 extend through corresponding apertures in thehorizontal leg 204 of the Z-rail and the main beam lower flange 92LF tofurther secure the Z-rails 200 to the main beam 92L. First boltassemblies 110 extend through corresponding apertures in the suspensionassembly 82 crossmember 99 and the lower horizontal flange 208 to securethe suspension components to the Z-rails 200. The suspension crossmember99 may also be welded 216 to the web 92W. Again, no component is weldedto the lower flange 92LF, which therefore retains its design temperingand toughness.

Similar to the Z-rail 100 shown in FIG. 3, the lower face of thehorizontal leg 204 of the Z-rail 200 has a width L1 equal to thedistance L1 from the web 92W to an inner face 94 of the main beam lowerflange 92LF, and the outer face of the vertical leg 206 has a width L2that is equal to the vertical width L2 of the main beam lower flange92LF (see FIGS. 2A and 3).

While illustrative embodiments have been illustrated and described, itwill be appreciated that various changes can be made therein withoutdeparting from the spirit and scope of the invention.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. An elongate attachmentmember for attaching an end of a crossmember to a main beam of atrailer, the main beam having a web portion and a flange extending awayfrom the web portion, wherein the flange defines an upper surface havinga first width and an end surface having a second width, the elongateattachment member comprising: (i) a first end section, (ii) an L-shapedportion comprising a horizontal leg extending from the first end sectionand a vertical leg extending from the horizontal leg, and (iii) a secondend section extending from a bottom end of the vertical leg; wherein thehorizontal leg of the L-shaped portion defines a lower surface having awidth equal to the first width and the vertical leg of the L-shapedportion defines an outer surface having a width equal to the secondwidth.
 2. The elongate attachment member of claim 1, wherein theelongate attachment member is configured to attach a plurality ofcrossmembers to the main beam.
 3. The elongate attachment member ofclaim 1, wherein the second end section is perpendicular to the verticalleg of the L-shaped portion.
 4. The elongate attachment member of claim3, wherein the first end section is perpendicular to the horizontal legof the L-shaped portion.
 5. The elongate attachment member of claim 1,wherein the horizontal leg is configured to be bolted to the flange andthe second end section is configured to be bolted to the crossmember. 6.The elongate attachment member of claim 1, wherein the second endsection comprises a first portion and a second portion spaced apart fromthe first portion.
 7. The elongate attachment member of claim 6, whereinthe elongate attachment member is configured to be fixedly attached to across member for a trailer suspension assembly.
 8. A crossmembersubassembly comprising: a first attachment member in accordance withclaim 1 and a second attachment member in accordance with claim 1; and aplurality of crossmembers fixedly connecting the first attachment memberto the second attachment member.
 9. The crossmember subassembly of claim8, wherein the plurality of crossmembers each comprises a first end thatis welded to the first attachment member, and a second end that iswelded to the second attachment member.